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Electronics Electronics Blog Fault DIagnosis

Repair of Samsung LE40M86BD Television (power cycling)

Introduction Recently I have had cause for complaint with our Samsung LE40M86BD LCD Television.  It had been working just fine, and then all of a sudden it developed a power-cycling problem.  The symptom is as follows: From power-on, the TV works perfectly for around 10 minutes. After a while the TV switches itself to standby, […]

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Electronics Blog Electronics Projects

Sorting out the Velleman MK170 Christmas Star

Last Christmas I bought a Velleman MK170 Christmas Star project for my Wife to build.  She often shows interest in my various electronics projects and I thought it would be a good way for her to build something that she could show off to friends and family, whilst at the same time teaching her a […]

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Electronics Electronics Blog Electronics Projects

Simple circuit for controlling LED brightness

Recently I was asked to produce a circuit to create a variable ‘dim’ control for an existing LED based exhibition. I decided to go with a simple 555-timer based design which provides control of the pulse width of an output, whilst keeping the oscillation frequency fixed. The circuit is shown below.  It’s an unusual design, […]

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Electronics Electronics Blog Electronics Projects

Happy Valentines Day Project

Happy Valentines Day! A few years ago I created a little valentines day project, shown in the video at the end of this post.  It’s basically just a multi-vibrator circuit with two groups of LEDs, arranged as an inner and outer heart: The full schematic is shown here, click on it for a full enlarged […]

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Electronics Blog Fault DIagnosis

Panasonic AE700 Projector Diagnosis & Repair

In the tinkering cave this week we have a Panasonic AE700 HD Projector. These units are pretty old now, but they come highly recommended in many online reviews and the HDMI support means they remain a useful home cinema option. The unit was first presented to me by a work colleague who complained that the […]

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Fault DIagnosis

JVC TH-S5 Diagnosis and Repair

Symptoms I’ve owned the JVC TH-S5 home theatre system for many years.  It could be as much as 8 or 9 years.  In all that time it’s been a reliable machine, although to be fair it’s also had quite an easy life; I don’t watch much TV (what self-respecting Engineer and tinkerer has time for […]

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Electronics Electronics Blog Electronics Tutorials KiCAD

Resolving duplicate part name problems in KiCAD

The Problem In KiCAD, a problem occurs when you try to create a new schematic symbol for a custom library and you happen to give it the same name as another part that exists in a different library. For example, let’s say you decide to create a part called “MAX3232”, and there happens to be […]

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Computer Mods Computing Electronics Electronics Blog

Hardware Hacking the IOMEGA StorCenter ix2-200

Introduction The StorCenter ix2-200 is a RAID network drive supplied by iomega.  I have used the 2TB version for about two years now to keep secure (backed up) copies of my precious data.  Any data I write to the device is mirrored on its paired 2TB drive inside the unit, so one drive can fail […]

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Electronics Blog

Agilent U1253B Input Impedance Problem

 Gotcha! I’ve experienced a problem recently whilst measuring high voltages with a 1000:1 high voltage probe and an Agilent (U1253B)/Fluke (28II) multimeter.  The problem is that the two meters don’t agree with each other! The Fluke (my meter of choice) returns voltage readings within expectation all the way up to 12kV (12V as displayed on […]

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Electronics Blog

The “Repair Man” Trap

Anyone who has ever worked in the electronics trade will almost certainly have been asked to repair consumer electronics products for friends, family and even random neighbours.  How do you deal with these requests? Do you politely decline or do you end up getting sucked in? Rookies usually get sucked in.  I’ve been there, done […]